Intralesional corticosteroid injections are a mainstay treatment of hypertrophic acne scarring and are believed to exert their effects by decreasing fibroblast proliferation and promoting collagen degradation.37 Treatment with steroids generally is effective, with reported improvement in 75% (6/8) of patients and complete flattening in 50% (4/8) of lesions according to one study.38 Development of hypopigmentation, dermal atrophy, and telangiectasia are potential sequelae of this treatment.37
5-Fluorouracil, bleomycin, and verapamil also have been used with good results as intralesional treatments of hypertrophic scars, but these agents typically are reserved for cases of corticosteroid failure. Such compounds are thought to mediate their effects through inhibition of dermal fibroblast proliferation.39 Results with these therapies are varied, but greater than 75% improvement is seen in most cases. Adverse effects include injection-site ulceration and hyperpigmentation.39
Cryotherapy
Contact cryotherapy has been studied as treatment of hypertrophic acne scars. The exact mechanism through which scars are reduced is unclear, but it is hypothesized that the physical damage caused by freezing and thrombosis lead to collagen restructuring. According to one study, cryotherapy was reported to achieve good or excellent results in 76% (29/38) of cases.40 Permanent pigmentary alterations are a possible AE.
Silicone Dressings
Silicone dressings are a reasonable treatment option for hypertrophic acne scarring given their proven efficacy and minimal risk for AEs. Thin sheets of silicone gels or membranes are applied daily in a topical manner to acne scars and are believed to be therapeutic through a combination of pressure and hydration, which subsequently inhibits fibroblast production of collagen. Notable reductions in scar appearance and size are seen in 60% to 80% of individuals using this method.41 Adverse effects are limited to pruritus and local skin maceration. Patient noncompliance may be an issue, as the silicone dressings may be applied on highly visible areas such as the face. Patients may apply the dressings at night, but efficacy may be reduced.
Conclusion
When determining which treatment options to use in a patient with acne scarring, it is important to first determine the patient’s treatment goals while simultaneously establishing realistic expectations. Important factors to consider are the patient’s preferences regarding treatment risk, duration, and permanence, as well as budget and social or work requirements. As such, treatment plans for each patient should be determined on a case-by-case basis. It also is important to note that a combination of different treatment modalities often is necessary and superior to monotherapy in achieving satisfactory cosmetic outcomes.
